Yesterday, I removed the Dip Tube and cleaned it. I also cleaned the threads of the cold 3/4" input.
I noticed there weren't a lot of threads for the nipple to engage.
The coldwater input dead-ended with the plastic top of the Dip Tube..
Careful: You can't bottom out the nipple, without crushing the plastic flange of the Dip Tube.
There was leftover OEM sealant paste and very tiny bits of thin white Teflon tape in the threads.
The tape has been turned into paste.?.
It looked like the Teflon had been shredded into thin little 2-3 mm strips.
(Back when I installed this 6" Iron nipple, I used 3 turns (or more) of Teflon tape, because of the size of the threads).
I wonder if this destruction was caused by vibration? And because there is not much thread engagement?
This morning, I took a picture of the old iron nipple. (3/4x6 inch).
It seems like there was only 3 or 4 threads doing the sealing work.
Not much Teflon tape visible. Looking at all the rust or staining, Slow leaking had been going on for some time.
It just suddenly started leaking a lot faster the other day..
The design of the 3/4" ports, seems much too shallow. More threads are needed.
I would not recommend this model of hotwater tank for this type of application (ASHP on top).
